// 46.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"

int main(int argc, char* argv[])
{float a,b,c;
char op;
scanf("%f%c%f",&a,&op,&b);
if('+'==op)
{c=a+b;
printf("%.2f",c);}

else if('-'==op)
{c=a-b;
printf("%.2f",c);}

else if('*'==op)
{c=a*b;
printf("%.2f",c);}

else if('/'==op&&b!=0)
{c=a/b;
printf("%.2f",c);}
else
printf("error");


	return 0;
}

